The present invention relates to lawn edgings having a L-shaped cross-section comprising a soil covering portion and a soil penetrating portion, and more particularly, the present invention relates to lawn edgings that have transversal shape resilience in use, and that are packaged and sold in a compact coiled form.
The prior art comprises two common types of lawn edgings. The first type has a flat soil covering strip to cover a soil surface which is not accessible to a lawn mower, such as along building foundations and fences for examples. The soil covering strip deprives the soil from rain and sunlight and prevents the growth of grass and other vegetation at that location. These lawn edgings are installed to obviate the need to use a weed trimmer for trimming the grass along the structures bordering a lawn. Examples of lawn edgings of the first type are described in the following documents:
U.S. Pat. No. 3,485,449 issued on Dec. 23, 1969 to J. L. Wilson;
U.S. Pat. No. 3,803,760 issued on Apr. 16, 1974 to J. J. Matvey;
U.S. Pat. No. 4,381,622 issued on May 3, 1983 to V. B. Spidell;
U.S. Pat. No. 4,690,382 issued on Sep. 1, 1987 to E. A. Koperdak;
U.S. Pat. No. 4,809,459 issued on Mar. 7, 1989 to A. Brylla et al.;
U.S. Pat. No. 4,897,973 issued on Feb. 6, 1990 to W. A. Foster, Jr. et al.;
U.S. Pat. No. 5,544,445 issued on Aug. 13, 1996 to J. A. Mantilla;
U.S. Pat. No. 5,857,288 issued on Jan. 12, 1999 to W. V. Wiste.
Lawn edgings of the second type have a narrow fence-like configuration, a portion of which is inserted in the ground. These lawn edgings are used as landscape dividers around flower beds, walkways, rock gardens, and to retain mulch around trees. Lawn edgings of the second type are illustrated and described in the following documents:
U.S. Pat. No. 3,788,001 issued on Jan. 29, 1974 to G. F. Balfanz, Jr.;
U.S. Pat. No. 5,456,045 issued on Oct. 10, 1995 to D. R. Bradley et al.;
CA Appl. 2,137,719 published on Jun. 14, 1995 by C. A. Torp, Jr. et al.; CA Appl. 2,146,494 published on Dec. 2, 1995 by D. J. Reum et al;
DT Patent No. 3,039,971 published on May 27, 1982 by B. Grueber.
The lawn edgings that are of particular interest herein consist of a combination of the two common types, having a L-shaped cross-section comprising a soil covering portion and a soil penetrating portion. Lawn edgings of that type are normally made with semi-rigid plastic material and are sold in straight lengths with connectors. L-shaped lawn edgings are preferred for use along foundation walls, for their ease of installation basically and for their ability to remain close to the wall. However, straight lengths of lawn edging are known to be inconvenient to stack in a display rack, and to carry from a hardware store to a customer""s residence. They are also difficult to install around curbs, walkways and other curved landscape features.
In the past, the packaging of a lawn edging in a compact roll form has been limited to the narrow type edgings where each turn in a roll is relatively thin. It is believed that there is no L-shaped lawn edging in the prior art which can be marketed in coils and deployed by a customer to form a malleable, durable and well anchored soil cover. As such, it is believed that there continues to be a need for a L-shaped lawn edging which has all the advantages of the straight length edgings, but which can be packaged in a compact coiled form.
The present invention provides for a lawn edging that has a L-shaped cross-section and that is collapsible and bendable to form an even-layered coil. The coiled edging takes minimum floor space in a retail store and is easily handled by customers. The lawn edging of the present invention is easily deployed into a resilient structure which is easy to install and which maintains a good appearance. The lawn edging of the present invention resists buckling and lifting and maintains a positive seal against the foundation wall along which it is installed.
Broadly, in a first aspect of the present invention, there is provided a lawn edging made of plastic material and comprising: a ridge extending along a length thereof; a soil covering portion extending from and along the ridge; a soil penetrating portion also extending from and along the ridge at an angle from the soil covering portion, and a lip extending from and along the ridge, away from the soil covering portion and the soil penetrating portion. The lip extends along a median of the angle mentioned above. The angle mentioned above is less than a right angle such that when the soil covering portion is bent at right angle with the soil penetrating portion, the lip extends away from a plane defined by the soil penetrating portion.
The major advantage of this feature is that the tip of the lip maintains a good seal against the foundation wall. The irregularities present on a foundation wall behind the soil penetrating portion do not prevent the tip of the lip to follow and conform to the surface of that wall for sealing the foundation wall against rain and blowing dust and weed seeds which may otherwise promote the growth of vegetation along the wall.
In accordance with another feature of the present invention, the soil covering portion and the soil penetrating portion have a same nominal thickness. The lawn edging further has a first transition region between the ridge and the soil covering portion, and a second transition region between the ridge and the soil penetrating portion. The first and second transition regions have a thickness variation from the nominal thickness at a distance from the ridge to about three times the nominal thickness near the ridge. The distance covered by each thickness variation is about five times the nominal thickness. These thickness variations are advantageous for providing substantial resilience between the ridge and the soil penetrating portion and the soil covering portion, for urging the soil covering portion against the soil surface when the lawn edging is installed.
In yet another aspect of the present invention there is provided a lawn edging in a collapsed mode. The lawn edging is made of plastic material and comprises: a ridge extending therealong; a soil covering portion extending from and along the ridge; a soil penetrating portion extending from the ridge and along and substantially parallel to the soil covering portion, and a lip extending from the ridge, opposite the soil covering portion and the soil penetrating portion. The soil penetrating portion has an anchoring projection having substantially a same thickness as the ridge. The soil covering portion has a width substantially equivalent to a distance between the anchoring projection and the ridge. The lawn edging is thereby bendable to form a coil having parallel coil layers.
In accordance with a further feature of the present invention, there is provided a lawn edging installed along a foundation wall at the soil level along that foundation wall. The lawn edging comprises: a ridge extending along the foundation wall; a soil covering portion extending from the ridge on the soil surface along the foundation wall; a soil penetrating portion extending downward from the ridge and along the foundation wall substantially at right angle with the soil covering portion, and a lip extending from the ridge and abutting against the foundation wall. The lip makes substantially a same angle between the soil covering portion and the soil penetrating portion.
The advantages of this installation are that a contact of the lip against the foundation wall causes a void to be formed between the soil penetrating portion and the foundation wall for improving a sealing engagement of the tip of the lip against the foundation wall for preventing water, dust, seeds and pollen from entering between the foundation wall and the soil penetrating portion. Also, a soil pressure against the soil penetrating portion toward the foundation wall urges the soil covering portion against the soil surface, for preventing buckling and lifting of the soil covering portion, thereby ensuring a good appearance of the lawn edging.
Still another feature of the invention is that it is susceptible of a low cost of manufacture with regard to materials, equipment and labour, and which accordingly is then susceptible of low price of sale to the industry, thereby making such lawn edging economically available to the public.
Other advantages and novel features of the invention will become apparent from the following detailed description.